"For the health of pastures and the long-term productivity of breeding females, producers should consider the condition of forages and the cattle when making decisions about when to wean," says Carl Dahlen, North Dakota State University beef cattle specialist.
The 2013 growing season was unusual for pasture production and quality across North Dakota. Much of the western region received above-average moisture throughout the summer, while the central and eastern portions received excessive moisture early, then limited rain in July and August. These moisture patterns create two different scenarios that result in differing forage quality issues, according to rangeland management.
On average, forage production on North Dakota's rangeland was at or above normal throughout much of the state. Eighty percent of the state's forage grows from late May through early July. Most of the state received sufficient moisture in May and June to grow grass.
"However, if you were the unfortunate livestock producer who did not receive much rain in July and August, you will have quantity and quality issues," says Kevin Sedivec, NDSU range management specialist.
The May and June moisture created ample standing growth. However, as the moisture became deficient, green regrowth was limited, and what is left is mature growth that is low in quality. These producers also will lack the 20% growth that occurs from late August through late September (regrowth that occurs with late-summer moisture and cooler weather).
In the end, cattle grazing low-quality, mature plant material that lacks regrowth will suffer from protein, vitamin and mineral deficiency, the specialists say. In addition, overgrazing pastures in the fall may reduce pasture yields during the next growing season.
"For those ranchers who received moisture throughout the summer, quantity and quality will be adequate until a killing freeze," Sedivec says. "Once we receive a killing freeze, quantity still will be fine, but quality will deteriorate within two weeks following the event."